SPP d.o.o., Koprivnička ulica 47, 42000 Varaždin, Croatia.
Faculty of Geotechnical Engineering, University of Zagreb, Hallerova aleja 7, 42000 Varaždin, Croatia.
Sensors (Basel). 2022 Jan 25;22(3):934. doi: 10.3390/s22030934.
This paper was prepared based on in situ measurements carried out by the authors using the CPTu and DMT static penetration probes. The list of study sites includes seven specific locations in the northern parts of Croatia and one study site on the southern border of the country. The sites were selected based on the criterion of soil type, which falls into the category of soft to firm, slightly over-consolidated silty clays and silty sands. Intermediate soils are prevalent in the wider region, and most engineers deal with them in their everyday practice. For this reason, local characterization is of most importance for engineering purposes. In this investigation, results of in-situ tests are compared in order to validate the quality of the constrained modulus obtained from a CPT test to the one obtained by a DMT flat dilatometer. A comparison was made between the CPT test cone resistance Qt1 and two DMT parameters-normalized modulus ED/σ'v0 and horizontal stress index KD. Dependencies were analyzed for the main soil groups and intermediate data groups. Clay soils were divided into two subgroups based on the identification parameter ID, while silty soils were analyzed in three subgroups. The results for each subgroup differed significantly, and the analyses showed deviations from published values, especially for the intermediate soil groups. The usefulness of the application is demonstrated with examples at two sites, showing improvements over the most commonly used formula for the constrained modulus from the CPT test.
本文基于作者使用 CPTu 和 DMT 静力触探探头进行的原位测量编写而成。研究地点包括克罗地亚北部的七个特定地点和该国南部边界的一个研究地点。这些地点是根据土壤类型标准选择的，土壤类型属于软至硬、稍过固结的粉质粘土和粉砂。中间土在更广泛的地区很常见，大多数工程师在日常实践中都会处理它们。因此，本地特征化对于工程目的最为重要。在这项调查中，对原位测试结果进行了比较，以验证从 CPT 测试获得的约束模量的质量与从 DMT 平板膨胀计获得的约束模量的质量。比较了 CPT 测试锥尖阻力 Qt1 和 DMT 的两个参数——归一化模量 ED/σ'v0 和水平应力指数 KD。对主要土壤组和中间数据组进行了相关性分析。粘土土壤根据识别参数 ID 分为两个亚组，而粉质土壤则分为三个亚组。每个亚组的结果差异很大，分析结果偏离了已发表的值，尤其是对于中间土壤组。通过两个地点的示例展示了应用的有用性，该应用显示出在 CPT 测试中使用最常用的约束模量公式进行改进。
